1. Field of the Invention
The present invention relates to a printing apparatus for feeding ink to plates mounted peripherally of a plate cylinder, and transferring the ink through a blanket cylinder to printing paper wrapped around an impression cylinder.
2. Description of the Related Art
A known printing apparatus of the type noted above includes a plate cylinder for supporting a plurality of plates mounted peripherally thereof, a plurality of ink feeders for feeding different color inks to image areas on the plurality of plates mounted on the plate cylinder, respectively, and a single impression cylinder. Such a printing apparatus is capable of color printing by using the single plate cylinder and the single impression cylinder. Thus, the entire apparatus requires a reduced area for its installation and operation.
Japanese Patent Publication (Unexamined) H3-143634 (1991), for example, describes a printing apparatus for printing images on printing paper with two color inks. This apparatus includes a plate cylinder for supporting two plates mounted peripherally thereof, two ink feeders for feeding the different inks to the respective plates on the plate cylinder, a single dampening water feeder for feeding dampening water to each plate on the plate cylinder, and an impression cylinder having half a diameter of the plate cylinder. A sheet of printing paper is fed for every two rotations of the impression cylinder.
However, the printing apparatus described in the above patent publication always prints with two color inks, and is incapable of monochromatic printing.